Objective: The present study developed an ear measurement method based on a 3D scanner and ear casting tools for ear product designs. Background: Detail dimensions and a shape of the ear are required for the ear product design; however, there is a limitation of a 3D ear scanning due to a complex shape of the ear. Method: The present study collected the shape and dimensions of the ear from 100 Korean participants (50 males and 50 females) aged 20 to 59. The overall shape of the ear was scanned in 3D; and inner complex shape of the ear was cast by applying the ear casting tools, then the cast shape was scanned in 3D. Anthropometric landmarks were marked on the 3D shapes of the overall and cast ear, respectively; then 18 ear dimensions were automatically measured by applying an ear measurement system coded using Matlab. Conclusion: The method for the ear measurement and the 3D ear shape establish was developed and applied to the analysis of the ear of 100 Koreans. Application: The developed ear measurement method and the measurements of the ear can be applied to the ear product designs.